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Currently a table can only be vacuumed or analyzed by its owner or
a superuser. This can now be extended to any user by means of an
appropriate GRANT.
Nathan Bossart
Reviewed by: Bharath Rupireddy, Kyotaro Horiguchi, Stephen Frost, Robert
Haas, Mark Dilger, Tom Lane, Corey Huinker, David G. Johnston, Michael
Paquier.
Discussion: https://postgr.es/m/20220722203735.GB3996698@nathanxps13
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When the unit is omitted from log_temp_files the value is taken as kb,
but the logged value is also without unit but specified in bytes. This
could cause some confusion, so clarify in the documentation which unit
is used when logging.
Reported-by: iphatiey5eu2au6@pasms.be
Reviewed-by: Bruce Momjian <bruce@momjian.us>
Discussion: https://postgr.es/m/166859439833.632.13122583000472281400@wrigleys.postgresql.org
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Commit bcedd8f5f made subquery aliases optional in the FROM clause.
It missed updating this part of the docs, though.
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The overall order is alphabetic, but there were a few additions that
didn't observe this.
Author: Peter Smith <peter.b.smith@fujitsu.com>
Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAHut+Pv8Oa7v06hJb3+HzCtM2u-3oHWMdvXVHhvi7ofB83pNbg@mail.gmail.com
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The overall order is alphabetic, but there were a few additions that
didn't observe this.
Author: Peter Smith <peter.b.smith@fujitsu.com>
Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAHut+Pv8Oa7v06hJb3+HzCtM2u-3oHWMdvXVHhvi7ofB83pNbg@mail.gmail.com
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BEFORE
28.4.1. ANALYZE Progress Reporting
28.4.2. CREATE INDEX Progress Reporting
28.4.3. VACUUM Progress Reporting
28.4.4. CLUSTER Progress Reporting
28.4.5. Base Backup Progress Reporting
28.4.6. COPY Progress Reporting
AFTER
28.4.1. ANALYZE Progress Reporting
28.4.2. CLUSTER Progress Reporting
28.4.3. COPY Progress Reporting
28.4.4. CREATE INDEX Progress Reporting
28.4.5. VACUUM Progress Reporting
28.4.6. Base Backup Progress Reporting
Author: Peter Smith <peter.b.smith@fujitsu.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/CAHut+Pv8Oa7v06hJb3+HzCtM2u-3oHWMdvXVHhvi7ofB83pNbg@mail.gmail.com
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This makes the distinction between operating-system user name and
database user name a bit clearer. It also clarifies that the user
name is determined first, and then the default database name.
Author: David G. Johnston <david.g.johnston@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAKFQuwZUhgz=sUi+wGQV-PBTNjMovuA-BOV88RV-Vw0m0drCAg@mail.gmail.com
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pg_hba.conf and pg_ident.conf gain support for three record keywords:
- "include", to include a file.
- "include_if_exists", to include a file, ignoring it if missing.
- "include_dir", to include a directory of files. These are classified
by name (C locale, mostly) and need to be prefixed by ".conf", hence
following the same rules as GUCs.
This commit relies on the refactoring pieces done in efc9816, ad6c528,
783e8c6 and 1b73d0b, adding a small wrapper to build a list of
TokenizedAuthLines (tokenize_include_file), and the code is shaped to
offer some symmetry with what is done for GUCs with the same options.
pg_hba_file_rules and pg_ident_file_mappings gain a new field called
file_name, to track from which file a record is located, taking
advantage of the addition of rule_number in c591300 to offer an
organized view of the HBA or ident records loaded.
Bump catalog version.
Author: Julien Rouhaud
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/20220223045959.35ipdsvbxcstrhya@jrouhaud
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The lwlock wait queue scalability issue fixed in a4adc31f690 was quite hard to
find because of the exponential backoff and because we adjust spins_per_delay
over time within a backend.
To make it easier to find similar issues in the future, add a wait event for
the pg_usleep() in perform_spin_delay(). Showing a wait event while spinning
without sleeping would increase the overhead of spinlocks, which we do not
want.
We may at some later point want to have more granular wait events, but that'd
be a substantial amount of work. This provides at least some insights into
something currently hard to observe.
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
https://postgr.es/m/20221120204310.xywrhyxyytsajuuq@awork3.anarazel.de
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The Hunspell project moved from Sourceforge to Github sometime
in 2016, so update our links to match the new URL. Backpatch
the doc changes to all supported versions.
Discussion: https://postgr.es/m/DC9A662A-360D-4125-A453-5A6CB9C6C4B4@yesql.se
Backpatch-through: v11
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The postmaster normally sends SIGQUIT to force-terminate its
child processes after a child crash or immediate-stop request.
If that doesn't result in child exit within a few seconds,
we follow it up with SIGKILL. This patch provides GUC flags
that allow either of these signals to be replaced with SIGABRT.
On typically-configured Unix systems, that will result in a
core dump being produced for each such child. This can be
useful for debugging problems, although it's not something you'd
want to have on in production due to the risk of disk space
bloat from lots of core files.
The old postmaster -T switch, which sent SIGSTOP in place of
SIGQUIT, is changed to be the same as send_abort_for_crash.
As far as I can tell from the code comments, the intent of
that switch was just to block things for long enough to force
core dumps manually, which seems like an unnecessary extra step.
(Maybe at the time, there was no way to get most kernels to
produce core files with per-PID names, requiring manual core
file renaming after each one. But now it's surely the hard way.)
I also took the opportunity to remove the old postmaster -n
(skip shmem reinit) switch, which hasn't actually done anything
in decades, though the documentation still claimed it did.
Discussion: https://postgr.es/m/2251016.1668797294@sss.pgh.pa.us
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Typos reported by Álvaro Herrera and Erik Rijkers.
Catversion bump for 3d14e171e9e2236139e8976f3309a588bcc8683b was
inadvertently omitted.
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Similar to how the INHERIT option controls whether or not the
permissions of the granted role are automatically available to the
grantee, the new SET permission controls whether or not the grantee
may use the SET ROLE command to assume the privileges of the granted
role.
In addition, the new SET permission controls whether or not it
is possible to transfer ownership of objects to the target role
or to create new objects owned by the target role using commands
such as CREATE DATABASE .. OWNER. We could alternatively have made
this controlled by the INHERIT option, or allow it when either
option is given. An advantage of this approach is that if you
are granted a predefined role with INHERIT TRUE, SET FALSE, you
can't go and create objects owned by that role.
The underlying theory here is that the ability to create objects
as a target role is not a privilege per se, and thus does not
depend on whether you inherit the target role's privileges. However,
it's surely something you could do anyway if you could SET ROLE
to the target role, and thus making it contingent on whether you
have that ability is reasonable.
Design review by Nathan Bossat, Wolfgang Walther, Jeff Davis,
Peter Eisentraut, and Stephen Frost.
Discussion: http://postgr.es/m/CA+Tgmob+zDSRS6JXYrgq0NWdzCXuTNzT5eK54Dn2hhgt17nm8A@mail.gmail.com
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Erik Rijkers
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Extracted from a more ambitious patch.
Author: David G. Johnston <david.g.johnston@gmail.com>
Discussion: https://postgr.es/m/CAKFQuwZC4K0XYBm0bwBMDOZySBqhOSekDhLuaw4vPi+ozi8gqQ@mail.gmail.com
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The TAP tests can, to some degree, be controlled by a set of environment
variables. These were however only documented in a README and not in the
main documentation. This adds documentation of these variables, as well
as changes one CPAN reference to a ulink for consistency. While there,
also tag CPAN as an acronym as it's listed in the acronyms section.
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/YyPd9unV14SX2bLF@paquier.xyz
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The /release/ links are redirected to /dist/ and /pod/release/ to
/release/../view/, so update our links accordingly to avoid 301
redirects.
Discussion: https://postgr.es/m/CA672723-BAD2-436E-B6E6-163841E11A1B@yesql.se
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Author: Bharath Rupireddy, Jeff Davis
Discussion: https://postgr.es/m/CALj2ACVTBNA1wfVCsikfhygAbZe6kFY8Oz6PhOyhHyA4vAGouA%40mail.gmail.com
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To improve readability of the TG_ variables definition lists, this moves
the datatypes up to the defined term to avoid having each entry start
with "Data type". This also removes redundant wording that that didn't
carry any information from the descriptions.
Author: Christoph Berg <myon@debian.org>
Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: https://postgr.es/m/Yw4Noe3A2s87A0qq@msg.df7cb.de
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This adds a new psql command \bind that sets query parameters and
causes the next query to be sent using the extended query protocol.
Example:
SELECT $1, $2 \bind 'foo' 'bar' \g
This may be useful for psql scripting, but one of the main purposes is
also to be able to test various aspects of the extended query protocol
from psql and to write tests more easily.
Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/e8dd1cd5-0e04-3598-0518-a605159fe314@enterprisedb.com
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Setting archive_library and archive_command at the same time is now an
error. Before, archive_library would take precedence over
archive_command.
Author: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Discussion: https://www.postgresql.org/message-id/20220914222736.GA3042279%40nathanxps13
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We already allow explicitly writing DEFAULT for SET COMPRESSION,
so it seems a bit inflexible and non-orthogonal to not have it
for STORAGE.
Aleksander Alekseev
Discussion: https://postgr.es/m/CAJ7c6TMX9ui+6y3TQFaXJYVpZyBukvqhQbVDJ8OUokeLRhtnpA@mail.gmail.com
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Commit fede15417 introduced FILTER by jamming it into the existing
example introducing HAVING, which seems pedagogically poor to me;
and it added no information about what the keyword actually does.
Not to mention that the claimed output didn't match the sample
data being used in this running example.
Revert that and instead make an independent example using FILTER.
To help drive home the point that it's a per-aggregate filter,
we need to use two aggregates not just one; for consistency
expand all the examples in this segment to do that.
Also adjust the example using WHERE ... LIKE so that it'd produce
nonempty output with this sample data, and show that output.
Back-patch, as the previous patch was. (Sadly, v10 is now out
of scope.)
Discussion: https://postgr.es/m/166794307526.652.9073408178177444190@wrigleys.postgresql.org
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Make it clear that the data corresponding to the transactions committed
before confirmed_flush_lsn is not available anymore.
Author: Ashutosh Sharma
Reviewd by: Ashutosh Bapat
Discussion: https://postgr.es/m/CAE9k0P=hiqRXUonnmtS-5Pu8SbO=yF6vcrVBcfEf2+93ng_f5Q@mail.gmail.com
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There are some cases (e.g. when the subscription is created using the
connect = false option) where the remote replication slot was not created
automatically and the user must create it manually before the subscription
can be activated. There was not enough information in the docs for users
to do this easily.
Author: Peter Smith
Reviewd by: Shi yu, Amit Kapila
Discussion: https://postgr.es/m/CAHut+PvqdqOanheWSHDyhQiF+Z-7w=-+k4U+bwbT=b6YQ_hrXQ@mail.gmail.com
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pg_ident_file_mappings.line_number was described as a line number in
pg_ident.conf for a "rule" number, but this should refer to a "map".
The same inconsistent term was used in the main paragraph describing the
view.
Extracted from a patch by the same author. Issue introduced by
a2c8499 where this view has been added.
Author: Julien Rouhaud
Discussion: https://postgr.es/m/20221026031948.cbrnzgy5e7glsq2d@jrouhaud
Backpatch-through: 15
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This gives some additional advice on using row filters and column
lists on publications securely.
Author: Antonin Houska <ah@cybertec.at>
Reviewed-by: Euler Taveira <euler@eulerto.com>
Discussion: https://www.postgresql.org/message-id/flat/20330.1652105397@antos
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These numbers are strictly-monotone identifiers assigned to each rule
of pg_hba_file_rules and each map of pg_ident_file_mappings when loading
the HBA and ident configuration files, indicating the order in which
they are checked at authentication time, until a match is found.
With only one file loaded currently, this is equivalent to the line
numbers assigned to the entries loaded if one wants to know their order,
but this becomes mandatory once the inclusion of external files is
added to the HBA and ident files to be able to know in which order the
rules and/or maps are applied at authentication. Note that NULL is used
when a HBA or ident entry cannot be parsed or validated, aka when an
error exists, contrary to the line number.
Bump catalog version.
Author: Julien Rouhaud
Discussion: https://postgr.es/m/20220223045959.35ipdsvbxcstrhya@jrouhaud
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This entry was listed as a "string", but it is a "number. The other
fields are correctly described, on a second look.
Reported-by: Nuko Yokohama
Author: Tatsuo Ishii
Discussion: https://postgr.es/m/CAF3Gu1awoVoDP5d0_eN=cR=QkGVwH+OtFvwJkkc5cB_ZMWjyeA@mail.gmail.com
Backpatch-through: 15
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As of this commit, any database or user entry beginning with a slash (/)
is considered as a regular expression. This is particularly useful for
users, as now there is no clean way to match pattern on multiple HBA
lines. For example, a user name mapping with a regular expression needs
first to match with a HBA line, and we would skip the follow-up HBA
entries if the ident regexp does *not* match with what has matched in
the HBA line.
pg_hba.conf is able to handle multiple databases and roles with a
comma-separated list of these, hence individual regular expressions that
include commas need to be double-quoted.
At authentication time, user and database names are now checked in the
following order:
- Arbitrary keywords (like "all", the ones beginning by '+' for
membership check), that we know will never have a regexp. A fancy case
is for physical WAL senders, we *have* to only match "replication" for
the database.
- Regular expression matching.
- Exact match.
The previous logic did the same, but without the regexp step.
We have discussed as well the possibility to support regexp pattern
matching for host names, but these happen to lead to tricky issues based
on what I understand, particularly with host entries that have CIDRs.
This commit relies heavily on the refactoring done in a903971 and
fc579e1, so as the amount of code required to compile and execute
regular expressions is now minimal. When parsing pg_hba.conf, all the
computed regexps needs to explicitely free()'d, same as pg_ident.conf.
Documentation and TAP tests are added to cover this feature, including
cases where the regexps use commas (for clarity in the docs, coverage
for the parsing logic in the tests).
Note that this introduces a breakage with older versions, where a
database or user name beginning with a slash are treated as something to
check for an equal match. Per discussion, we have discarded this as
being much of an issue in practice as it would require a cluster to
have database and/or role names that begin with a slash, as well as HBA
entries using these. Hence, the consistency gained with regexps in
pg_ident.conf is more appealing in the long term.
**This compatibility change should be mentioned in the release notes.**
Author: Bertrand Drouvot
Reviewed-by: Jacob Champion, Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/fff0d7c1-8ad4-76a1-9db3-0ab6ec338bf7@amazon.com
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56788d215 adjusted the parallel seq scan code so that instead of handing
out a single block at a time to parallel workers, it now hands out ranges
of blocks.
Here we update the documentation which still claimed that workers received
just 1 block at a time.
Reported-by: Zhang Mingli
Discussion: https://postgr.es/m/17c99615-2c3b-4e4e-9d0b-424a66a7bccd@Spark
Backpatch-through: 14, where 56788d215 was added.
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Various test suites use the "openssl" program as part of their setup.
There isn't a way to override which openssl program is to be used,
other than by fiddling with the path, perhaps. This has gotten
increasingly problematic because different versions of openssl have
different capabilities and do different things by default.
This patch checks for an openssl binary in configure and meson setup,
with appropriate ways to override it. This is similar to how "lz4"
and "zstd" are handled, for example. The meson build system actually
already did this, but the result was only used in some places. This
is now applied more uniformly.
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://www.postgresql.org/message-id/flat/dc638b75-a16a-007d-9e1c-d16ed6cf0ad2%40enterprisedb.com
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As currently designed, with a callback registered in a ERROR_CLEANUP
block, the shutdown callback would get called twice when updating
archive_library on SIGHUP, which is something that we want to avoid to
ease the life of extension writers.
Anyway, an ERROR in the archiver process is treated as a FATAL, stopping
it immediately, hence there is no need for a ERROR_CLEANUP block.
Instead of that, the shutdown callback is not called upon
before_shmem_exit(), giving to the modules the opportunity to do any
cleanup actions before the server shuts down its subsystems.
While on it, this commit adds some testing coverage for the shutdown
callback. Neither shell_archive nor basic_archive have been using it,
and one is added to shell_archive, whose trigger is checked in a TAP
test through a shutdown sequence.
Author: Nathan Bossart, Bharath Rupireddy
Reviewed-by: Kyotaro Horiguchi, Michael Paquier
Discussion: https://postgr.es/m/20221015221328.GB1821022@nathanxps13
Backpatch-through: 15
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It was previously easily overlooked at the end of several tables.
Reported-by: Alex Denman
Discussion: https://postgr.es/m/166335888474.659.16897487975376230364@wrigleys.postgresql.org
Backpatch-through: 10
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The fix is to run ANALYZE.
Discussion: https://postgr.es/m/YzRr+ys98UzVQJvK@momjian.us,
https://postgr.es/m/flat/CAKJS1f8DTbCHf9gedU0He6ARsd58E6qOhEHM1caomqj_r9MOiQ%40mail.gmail.com,
https://postgr.es/m/CAKJS1f80o98hcfSk8j%3DfdN09S7Sjz%2BvuzhEwbyQqvHJb_sZw0g%40mail.gmail.com
Backpatch-through: 10
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It can be useful to know when a relation has last been used, e.g., when
evaluating whether an index is still required. It was already possible to
infer the time of the last usage by tracking, e.g.,
pg_stat_all_indexes.idx_scan over time. But far from everybody does so.
To make it easier to detect the last time a relation has been scanned, track
that time in each relation's pgstat entry. To minimize overhead a) the
timestamp is updated only when the backend pending stats entry is flushed to
shared stats b) the last transaction's stop timestamp is used as the
timestamp.
Bumps catalog and stats format versions.
Author: Dave Page <dpage@pgadmin.org>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Bruce Momjian <bruce@momjian.us>
Reviewed-by: Vik Fearing <vik@postgresfriends.org>
Discussion: https://postgr.es/m/CA+OCxozrVHNFVEPkweUHMZje+t1tfY816d9MZYc6eZwOOusOaQ@mail.gmail.com
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This has apparently been wrong since the beginning
(090d0f2050647958865cb495dff74af7257d2bb4).
Discussion: https://www.postgresql.org/message-id/289c2e45-c7d9-5ce4-7eff-a9e2a33e1580@enterprisedb.com
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Using pg_buffercache_summary() is significantly cheaper than querying
pg_buffercache and summarizing in SQL.
Author: Melih Mutlu <m.melihmutlu@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Aleksander Alekseev <aleksander@timescale.com>
Reviewed-by: Zhang Mingli <zmlpostgres@gmail.com>
Discussion: https://postgr.es/m/CAGPVpCQAXYo54Q%3D8gqBsS%3Du0uk9qhnnq4%2B710BtUhUisX1XGEg%40mail.gmail.com
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While at it, simplify wording a bit.
Author: Takamichi Osumi <osumi.takamichi@fujitsu.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Discussion: https://postgr.es/m/TYCPR01MB8373F93F5D094A2BE648990DED259@TYCPR01MB8373.jpnprd01.prod.outlook.com
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Commit 3d956d956 allowed the COPY, but it's done by inserting individual
rows to the foreign table, so it can be inefficient due to the overhead
caused by each round-trip to the foreign server. To improve performance
of the COPY in such a case, this patch allows batch insertion, by
extending the multi-insert machinery in CopyFrom() to the foreign-table
case so that we insert multiple rows to the foreign table at once using
the FDW callback routine added by commit b663a4136. This patch also
allows this for postgres_fdw. It is enabled by the "batch_size" option
added by commit b663a4136, which is disabled by default.
When doing batch insertion, we update progress of the COPY command after
performing the FDW callback routine, to count rows not suppressed by the
FDW as well as a BEFORE ROW INSERT trigger. For consistency, this patch
changes the timing of updating it for plain tables: previously, we
updated it immediately after adding each row to the multi-insert buffer,
but we do so only after writing the rows stored in the buffer out to the
table using table_multi_insert(), which I think would be consistent even
with non-batching mode, because in that mode we update it after writing
each row out to the table using table_tuple_insert().
Andrey Lepikhov, heavily revised by me, with review from Ian Barwick,
Andrey Lepikhov, and Zhihong Yu.
Discussion: https://postgr.es/m/bc489202-9855-7550-d64c-ad2d83c24867%40postgrespro.ru
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The output plugin name is a mandatory option when creating a logical
slot, but the grammar documented was not described as such. While on
it, fix two comments in repl_gram.y to show that TEMPORARY is an
optional grammar choice.
Author: Ayaki Tachikake
Discussion: https://postgr.es/m/OSAPR01MB2852607B2329FFA27834105AF1229@OSAPR01MB2852.jpnprd01.prod.outlook.com
Backpatch-through: 15
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Add
After=network-online.target
Wants=network-online.target
to the suggested unit file for starting a Postgres server.
This delays startup until the network interfaces have been
configured; without that, any attempt to bind to a specific
IP address will fail.
If listen_addresses is set to "localhost" or "*", it might be
possible to get away with the less restrictive "network.target",
but I don't think we need to get into such detail here.
Per suggestion from Pablo Federico.
Discussion: https://postgr.es/m/166552157407.591805.10036014441784710940@wrigleys.postgresql.org
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Other pg_get_XXXdef() functions are documented, so it seems reasonable
to include this as well.
Ian Barwick
Discussion: https://postgr.es/m/CAB8KJ=hb2QZXdgyrrRjPCw++DsrRcui4fKArWabQ+oij+2x=_w@mail.gmail.com
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Reported-by: Elena Indrupskaya
Discussion: https://postgr.es/m/0af43b49-1646-93d0-ccf1-bb3c635c8c6f@postgrespro.ru
Author: Elena Indrupskaya
Backpatch-through: 15
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meson/ninja do not support specifying dependencies via globs (as those make it
significantly more expensive to check the current build state). Instead
targets should emit dependency information when running that then can be
cheaply re-checked during future builds.
To handle xmllint and xsltproc invocations in the docs, add and use a wrapper
that uses --load-trace to collect dependency information.
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Author: Nazir Bilal Yavuz <byavuz81@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/c5736f70-bb6d-8d25-e35c-e3d886e4e905@enterprisedb.com
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This reverts commit db0d67db2401eb6238ccc04c6407a4fd4f985832 and
several follow-on fixes. The idea of making a cost-based choice
of the order of the sorting columns is not fundamentally unsound,
but it requires cost information and data statistics that we don't
really have. For example, relying on procost to distinguish the
relative costs of different sort comparators is pretty pointless
so long as most such comparator functions are labeled with cost 1.0.
Moreover, estimating the number of comparisons done by Quicksort
requires more than just an estimate of the number of distinct values
in the input: you also need some idea of the sizes of the larger
groups, if you want an estimate that's good to better than a factor of
three or so. That's data that's often unknown or not very reliable.
Worse, to arrive at estimates of the number of calls made to the
lower-order-column comparison functions, the code needs to make
estimates of the numbers of distinct values of multiple columns,
which are necessarily even less trustworthy than per-column stats.
Even if all the inputs are perfectly reliable, the cost algorithm
as-implemented cannot offer useful information about how to order
sorting columns beyond the point at which the average group size
is estimated to drop to 1.
Close inspection of the code added by db0d67db2 shows that there
are also multiple small bugs. These could have been fixed, but
there's not much point if we don't trust the estimates to be
accurate in-principle.
Finally, the changes in cost_sort's behavior made for very large
changes (often a factor of 2 or so) in the cost estimates for all
sorting operations, not only those for multi-column GROUP BY.
That naturally changes plan choices in many situations, and there's
precious little evidence to show that the changes are for the better.
Given the above doubts about whether the new estimates are really
trustworthy, it's hard to summon much confidence that these changes
are better on the average.
Since we're hard up against the release deadline for v15, let's
revert these changes for now. We can always try again later.
Note: in v15, I left T_PathKeyInfo in place in nodes.h even though
it's unreferenced. Removing it would be an ABI break, and it seems
a bit late in the release cycle for that.
Discussion: https://postgr.es/m/TYAPR01MB586665EB5FB2C3807E893941F5579@TYAPR01MB5866.jpnprd01.prod.outlook.com
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This fixes some areas related to logical replication and custom RMGRs.
Author: Ekaterina Kiryanova
Discussion: https://postgr.es/m/fa4773f1-1396-384a-bcd7-85b5e013f399@postgrespro.ru
Backpatch-through: 15
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Currently, PQsslAttributeNames() returns the same list of attribute
names regardless of its conn parameter. This patch changes it to
have behavior parallel to what 80a05679d installed for PQsslAttribute:
you get OpenSSL's attributes if conn is NULL or is an SSL-encrypted
connection, or an empty list if conn is a non-encrypted connection.
The point of this is to have sensible connection-dependent behavior
in case we ever support multiple SSL libraries. The behavior for
NULL can be defined as "the attributes for the default SSL library",
parallel to what PQsslAttribute(NULL, "library") does.
Since this is mostly just future-proofing, no back-patch.
Discussion: https://postgr.es/m/17625-fc47c78b7d71b534@postgresql.org
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